(a) Technical Field
The present invention relates to a method for adjusting an output of a fuel cell system, and more particularly, to a method for adjusting an output of a fuel cell system by comparing an air flow rate required for driving and an actually introduced air flow rate to produce an average air flow rate.
(b) Description of the Related Art
In a fuel cell vehicle equipped with a fuel cell system, electricity is produced by supplying hydrogen used as fuel to a fuel cell stack, and the vehicle is driven by operating an electric motor with electricity produced by the fuel cell stack.
The fuel cell system is a type of power generation system directly electrochemically converting chemical energy of fuel into electric energy within the fuel cell stack, rather than converting the chemical energy of fuel into heat through combustion.
In the fuel cell system, hydrogen of high impurity is supplied from a hydrogen storage tank to an anode of a fuel cell during operation, and air in the atmosphere is directly supplied to a cathode of the fuel cell using an air supply device such as an air blower.
Thus, hydrogen supplied to the fuel cell stack is separated into a hydrogen ion and an electron in a catalyst of the anode, and the separated hydrogen ion crosses to the cathode through a polymer electrolyte membrane, and oxygen supplied to the cathode is combined with an electron introduced to the cathode through an external conducting wire to produce water to generate electric energy.
That is, the fuel cell system has a control function of receiving air and hydrogen while managing heat, a control function of distributing power between a high voltage battery and the fuel cell system, and a control function of driving a vehicle according to a driver's intention.
However, in a process of producing electricity by supplying hydrogen to the fuel cell stack of such a fuel cell system, moisture produced within the fuel cell stack significantly affects performance of the fuel cell vehicle.